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Paez‐Perez M, Kuimova MK. Molecular Rotors: Fluorescent Sensors for Microviscosity and Conformation of Biomolecules. Angew Chem Int Ed Engl 2024; 63:e202311233. [PMID: 37856157 PMCID: PMC10952837 DOI: 10.1002/anie.202311233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 10/17/2023] [Accepted: 10/17/2023] [Indexed: 10/20/2023]
Abstract
The viscosity and crowding of biological environment are considered vital for the correct cellular function, and alterations in these parameters are known to underly a number of pathologies including diabetes, malaria, cancer and neurodegenerative diseases, to name a few. Over the last decades, fluorescent molecular probes termed molecular rotors proved extremely useful for exploring viscosity, crowding, and underlying molecular interactions in biologically relevant settings. In this review, we will discuss the basic principles underpinning the functionality of these probes and will review advances in their use as sensors for lipid order, protein crowding and conformation, temperature and non-canonical nucleic acid structures in live cells and other relevant biological settings.
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Affiliation(s)
- Miguel Paez‐Perez
- Department of Chemistry, Imperial College London, MSRHImperial College LondonWood LaneLondonW12 0BZUK
| | - Marina K. Kuimova
- Department of Chemistry, Imperial College London, MSRHImperial College LondonWood LaneLondonW12 0BZUK
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2
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Holden L, Gkika KS, Burke CS, Long C, Keyes TE. Selective, Disruptive Luminescent Ru(II) Polypyridyl Probes of G-Quadruplex. Inorg Chem 2023; 62:2213-2227. [PMID: 36703307 PMCID: PMC9906756 DOI: 10.1021/acs.inorgchem.2c03903] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Sensors capable of transducing G-quadruplex DNA binding are important both in solution and for imaging and interrogation in cellulo. Ru(II)-based light switches incorporating dipyridylphenazine (dppz) ligands are effective probes for recognition and imaging of DNA and its polymorphs including G-quadruplex, although selectivity is a limitation. While the majority of Ru(II)-based light switches reported to date, stabilize the quadruplex, imaging/theranostic probes that can disrupt G4s are of potentially enormous value in study and therapy for a range of disease states. We report here, on a Ru(II) complex (Ru-PDC3) that assembles the light switch capability of a Ru(II) dipyridylphenazine complex with the well-known G4-selective ligand Phen-DC3, into a single structure. The complex shows the anticipated light switch effect and strong affinity for G4 structures. Affinity depended on the G4 topology and sequence, but across all structures bar one, it was roughly an order of magnitude greater than for duplex or single-stranded DNA. Moreover, photophysical and Raman spectral data showed clear discrimination between duplex DNA and G4-bound structures offering the prospect of discrimination in imaging as well as in solution. Crucially, unlike the constituent components of the probe, Ru-PDC3 is a powerful G4 disrupter. From circular dichroism (CD), a reduction of ellipticity of the G4 between 70 and 95% was observed depending on topology and in many cases was accompanied by an induced CD signal for the metal complex. The extent of change in ellipticity is amongst the largest reported for small-molecule ligand G4 binding. While a promising G4 probe, without modification, the complex is fully water-soluble and readily permeable to live cells.
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3
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Borissov A, Maurya YK, Moshniaha L, Wong WS, Żyła-Karwowska M, Stępień M. Recent Advances in Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds. Chem Rev 2022; 122:565-788. [PMID: 34850633 PMCID: PMC8759089 DOI: 10.1021/acs.chemrev.1c00449] [Citation(s) in RCA: 224] [Impact Index Per Article: 112.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Indexed: 12/21/2022]
Abstract
This review surveys recent progress in the chemistry of polycyclic heteroaromatic molecules with a focus on structural diversity and synthetic methodology. The article covers literature published during the period of 2016-2020, providing an update to our first review of this topic (Chem. Rev. 2017, 117 (4), 3479-3716).
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Affiliation(s)
| | | | | | | | | | - Marcin Stępień
- Wydział Chemii, Uniwersytet
Wrocławski, ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland
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4
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Summers PA, Thomas AP, Kench T, Vannier JB, Kuimova MK, Vilar R. Cationic helicenes as selective G4 DNA binders and optical probes for cellular imaging. Chem Sci 2021; 12:14624-14634. [PMID: 34881015 PMCID: PMC8580066 DOI: 10.1039/d1sc04567a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 10/12/2021] [Indexed: 01/17/2023] Open
Abstract
The important role that G-quadruplex DNA (G4 DNA) structures play in regulating biological processes is becoming widely recognised. These structures have also been proposed to be attractive drug targets. Therefore, there has been significant interest in developing small molecules that can selectively bind to G4 DNA over other topologies. In this paper we investigate the interaction between DNA and helical compounds (helicenes) based on a central carbocation trisubstituted with aromatic rings. We show that the non-planar structure of these helicenes results in a significantly reduced affinity for dsDNA when compared to their planar analogues, whilst maintaining a high affinity for G4 DNA. Additionally, the right- and left-handed enantiomers of one of these helicenes recognise the chiral DNA environments of G4 and dsDNA differently. We show that upon DNA binding the helicenes display a fluorescence switch-on effect, which we have successfully used for cellular imaging in live and fixed U2OS cells, staining mitochondria and the nucleus, respectively.
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Affiliation(s)
- Peter A Summers
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane, White City Campus W12 0BZ UK +44 (0)20 7594 1967 +44 (0)20 7594 8558
| | - Ajesh P Thomas
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane, White City Campus W12 0BZ UK +44 (0)20 7594 1967 +44 (0)20 7594 8558
| | - Timothy Kench
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane, White City Campus W12 0BZ UK +44 (0)20 7594 1967 +44 (0)20 7594 8558
| | - Jean-Baptiste Vannier
- Telomere Replication and Stability Group, Medical Research Council - London Institute of Medical Sciences London W12 0NN UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London London W12 0NN UK
| | - Marina K Kuimova
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane, White City Campus W12 0BZ UK +44 (0)20 7594 1967 +44 (0)20 7594 8558
| | - Ramon Vilar
- Department of Chemistry, Molecular Sciences Research Hub, Imperial College London 82 Wood Lane, White City Campus W12 0BZ UK +44 (0)20 7594 1967 +44 (0)20 7594 8558
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5
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DNA Binding Mode Analysis of a Core-Extended Naphthalene Diimide as a Conformation-Sensitive Fluorescent Probe of G-Quadruplex Structures. Int J Mol Sci 2021; 22:ijms221910624. [PMID: 34638964 PMCID: PMC8508963 DOI: 10.3390/ijms221910624] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/24/2021] [Accepted: 09/27/2021] [Indexed: 12/27/2022] Open
Abstract
G-quadruplex existence was proved in cells by using both antibodies and small molecule fluorescent probes. However, the G-quadruplex probes designed thus far are structure- but not conformation-specific. Recently, a core-extended naphthalene diimide (cex-NDI) was designed and found to provide fluorescent signals of markedly different intensities when bound to G-quadruplexes of different conformations or duplexes. Aiming at evaluating how the fluorescence behaviour of this compound is associated with specific binding modes to the different DNA targets, cex-NDI was here studied in its interaction with hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex models by biophysical techniques, molecular docking, and biological assays. cex-NDI showed different binding modes associated with different amounts of stacking interactions with the three DNA targets. The preferential binding sites were the groove, outer quartet, or intercalative site of the hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex, respectively. Interestingly, our data show that the fluorescence intensity of DNA-bound cex-NDI correlates with the amount of stacking interactions formed by the ligand with each DNA target, thus providing the rationale behind the conformation-sensitive properties of cex-NDI and supporting its use as a fluorescent probe of G-quadruplex structures. Notably, biological assays proved that cex-NDI mainly localizes in the G-quadruplex-rich nuclei of cancer cells.
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6
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Kitamoto Y, Oda K, Ogino K, Hiyama K, Kita H, Hattori T, Oi S. Synthesis of an azadioxa-planar triphenylborane and investigation of its structural and photophysical properties. Chem Commun (Camb) 2021; 57:2297-2300. [PMID: 33533350 DOI: 10.1039/d0cc08331c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We report here the first successful synthesis of planar triphenylborane 1 with the phenyl groups bridged by oxygen and nitrogen atoms via double nucleophilic aromatic substitution reaction. The hetero atom-bridged 1 has excellent planarity. Its structural and photophysical properties are tunable by altering the bridging atoms.
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Affiliation(s)
- Y Kitamoto
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan.
| | - K Oda
- Advanced Technology Center, Corporate R&D Headquarters, KONICA MINOLTA, INC., 2970 Ishikawa-Machi, Hachioji-shi, Tokyo 192-8505, Japan
| | - K Ogino
- Advanced Technology Center, Corporate R&D Headquarters, KONICA MINOLTA, INC., 2970 Ishikawa-Machi, Hachioji-shi, Tokyo 192-8505, Japan
| | - K Hiyama
- Advanced Technology Center, Corporate R&D Headquarters, KONICA MINOLTA, INC., 2970 Ishikawa-Machi, Hachioji-shi, Tokyo 192-8505, Japan
| | - H Kita
- Advanced Technology Center, Corporate R&D Headquarters, KONICA MINOLTA, INC., 2970 Ishikawa-Machi, Hachioji-shi, Tokyo 192-8505, Japan
| | - T Hattori
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan.
| | - S Oi
- Department of Chemical Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan.
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7
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Shaikh AC, Veleta JM, Moutet J, Gianetti TL. Trioxatriangulenium (TOTA +) as a robust carbon-based Lewis acid in frustrated Lewis pair chemistry. Chem Sci 2021; 12:4841-4849. [PMID: 34168760 PMCID: PMC8179643 DOI: 10.1039/d0sc05893a] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/07/2021] [Indexed: 12/15/2022] Open
Abstract
We report the reactivity between the water stable Lewis acidic trioxatriangulenium ion (TOTA+) and a series of Lewis bases such as phosphines and N-heterocyclic carbene (NHC). The nature of the Lewis acid-base interaction was analyzed via variable temperature (VT) NMR spectroscopy, single-crystal X-ray diffraction, UV-visible spectroscopy, and DFT calculations. While small and strongly nucleophilic phosphines, such as PMe3, led to the formation of a Lewis acid-base adduct, frustrated Lewis pairs (FLPs) were observed for sterically hindered bases such as P( t Bu)3. The TOTA+-P( t Bu)3 FLP was characterized as an encounter complex, and found to promote the heterolytic cleavage of disulfide bonds, formaldehyde fixation, dehydrogenation of 1,4-cyclohexadiene, heterolytic cleavage of the C-Br bonds, and interception of Staudinger reaction intermediates. Moreover, TOTA+ and NHC were found to first undergo single-electron transfer (SET) to form [TOTA]·[NHC]˙+, which was confirmed via electron paramagnetic resonance (EPR) spectroscopy, and subsequently form a [TOTA-NHC]+ adduct or a mixture of products depending the reaction conditions used.
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Affiliation(s)
- Aslam C Shaikh
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
| | - José M Veleta
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
| | - Jules Moutet
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
| | - Thomas L Gianetti
- University of Arizona, Department of Chemistry and Biochemistry Tucson AZ USA
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Lewis BW, Bisballe N, Santella M, Summers PA, Vannier JB, Kuimova MK, Laursen BW, Vilar R. Assessing The Key Photophysical Properties of Triangulenium Dyes for DNA Binding by Alteration of the Fluorescent Core. Chemistry 2021; 27:2523-2536. [PMID: 33105523 DOI: 10.1002/chem.202003875] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Indexed: 11/09/2022]
Abstract
Four-stranded G-quadruplex (G4) DNA is a non-canonical DNA topology that has been proposed to form in cells and play key roles in how the genome is read and used by the cellular machinery. Previously, a fluorescent triangulenium probe (DAOTA-M2) was used to visualise G4s in cellulo, thanks to its distinct fluorescence lifetimes when bound to different DNA topologies. Herein, the library of available triangulenium probes is expanded to explore how modifications to the fluorescent core of the molecule affect its photophysical characteristics, interaction with DNA and cellular localisation. The benzo-bridged and isopropyl-bridged diazatriangulenium dyes, BDATA-M2 and CDATA-M2 respectively, featuring ethyl-morpholino substituents, were synthesised and characterised. The interactions of these molecules with different DNA topologies were studied to determine their binding affinity, fluorescence enhancement and fluorescence lifetime response. Finally, the cellular uptake and localisation of these optical probes were investigated. Whilst structural modifications to the triangulenium core only slightly alter the binding affinity to DNA, BDATA-M2 and CDATA-M2 cannot distinguish between DNA topologies through their fluorescence lifetime. It is argued theoretically and experimentally that this is due to reduced effectiveness of photoinduced electron transfer (PET) quenching. This work presents valuable new evidence into the critical role of PET quenching when using the fluorescence lifetime of triangulenium dyes to discriminate G4 DNA from duplex DNA, highlighting the importance of fine tuning redox and spectral properties when developing new triangulenium-based G4 probes.
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Affiliation(s)
- Benjamin W Lewis
- Department of Chemistry, Molecular Sciences Research Hub, White City Campus, Imperial College London, London, W12 0BZ, UK.,Institute of Chemical Biology, White City Campus, Imperial College London, London, W12 0BZ, UK
| | - Niels Bisballe
- Department of Chemistry & Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark
| | - Marco Santella
- Department of Chemistry & Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark
| | - Peter A Summers
- Department of Chemistry, Molecular Sciences Research Hub, White City Campus, Imperial College London, London, W12 0BZ, UK
| | - Jean-Baptiste Vannier
- Telomere Replication and Stability Group, Medical Research Council-London Institute of Medical Sciences, London, W12 0NN, UK.,Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, W12 0NN, UK
| | - Marina K Kuimova
- Department of Chemistry, Molecular Sciences Research Hub, White City Campus, Imperial College London, London, W12 0BZ, UK.,Institute of Chemical Biology, White City Campus, Imperial College London, London, W12 0BZ, UK
| | - Bo W Laursen
- Department of Chemistry & Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark
| | - Ramon Vilar
- Department of Chemistry, Molecular Sciences Research Hub, White City Campus, Imperial College London, London, W12 0BZ, UK.,Institute of Chemical Biology, White City Campus, Imperial College London, London, W12 0BZ, UK
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9
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Visualising G-quadruplex DNA dynamics in live cells by fluorescence lifetime imaging microscopy. Nat Commun 2021; 12:162. [PMID: 33420085 PMCID: PMC7794231 DOI: 10.1038/s41467-020-20414-7] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 11/27/2020] [Indexed: 12/12/2022] Open
Abstract
Guanine rich regions of oligonucleotides fold into quadruple-stranded structures called G-quadruplexes (G4s). Increasing evidence suggests that these G4 structures form in vivo and play a crucial role in cellular processes. However, their direct observation in live cells remains a challenge. Here we demonstrate that a fluorescent probe (DAOTA-M2) in conjunction with fluorescence lifetime imaging microscopy (FLIM) can identify G4s within nuclei of live and fixed cells. We present a FLIM-based cellular assay to study the interaction of non-fluorescent small molecules with G4s and apply it to a wide range of drug candidates. We also demonstrate that DAOTA-M2 can be used to study G4 stability in live cells. Reduction of FancJ and RTEL1 expression in mammalian cells increases the DAOTA-M2 lifetime and therefore suggests an increased number of G4s in these cells, implying that FancJ and RTEL1 play a role in resolving G4 structures in cellulo. Direct observation of G-quadruplexes (G4s) in live cells is challenging. Here the authors report a method to identify G4s within the nuclei of live and fixed cells using a fluorescent probe combined with fluorescence lifetime imaging microscopy.
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10
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Barsuk I, Lainé PP, Maurel F, Brémond É. Triangulenium dyes: the comprehensive photo-absorption and emission story of a versatile family of chromophores. Phys Chem Chem Phys 2020; 22:20673-20684. [PMID: 32895673 DOI: 10.1039/d0cp02990d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The triangulenium dyes constitute a family of versatile chromophores whose impressive photo-absorption and emission properties are currently highlighted in numerous novel experimental applications. In this investigation, we provide a comprehensive TDDFT characterization of their spectroscopic properties elucidating the origin of their large and complex absorption and emission vibronic spectra spread over the (whole) visible region. More precisely, by benchmarking the performance of 10 commonly-used exchange-correlation density functionals belonging to different classes of approximation, we develop and validate a computational protocol allowing the accurate modeling of both the position and optical line-shape of their vibrationally-resolved absorption and emission band structures. We find that semilocal approximations provide the best estimate of the structure of the vibronic spectra, however they spuriously and strongly underestimate their position. We finally show that global-hybrid density functionals mixing between 20 and 30% of exact-like exchange are an excellent compromise to get a satisfactory estimate of both of these properties.
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Affiliation(s)
- Irina Barsuk
- Université de Paris, ITODYS, CNRS, F-75006 Paris, France.
| | | | | | - Éric Brémond
- Université de Paris, ITODYS, CNRS, F-75006 Paris, France.
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11
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Spence P, Fielden J, Waller ZAE. Beyond Solvent Exclusion: i-Motif Detecting Capability and an Alternative DNA Light-Switching Mechanism in a Ruthenium(II) Polypyridyl Complex. J Am Chem Soc 2020; 142:13856-13866. [DOI: 10.1021/jacs.0c04789] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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12
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Leung E, Pilkington LI, Naiya MM, Barker D, Zafar A, Eurtivong C, Reynisson J. The cytotoxic potential of cationic triangulenes against tumour cells. MEDCHEMCOMM 2019; 10:1881-1891. [PMID: 32952994 PMCID: PMC7478161 DOI: 10.1039/c9md00305c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 08/19/2019] [Indexed: 12/20/2022]
Abstract
TOTA (trioxatriangulenium ion) is a close-shelled carbocation known to intercalate strongly with the DNA double helix (J. Reynisson, G. B. Schuster, S. B. Howerton, L. D. Williams, R. N. Barnett, C. L. Cleveland, U. Landman, N. Harrit, J. B. Chaires, J. Am. Chem. Soc. 2003, 125, 2072). The cytotoxicity of TOTA and its four close structural analogues, ADOTA, Pr-ADOTA, Pr-DAOTA and n-Butyl-TATA were tested against the breast cancer cell line MDA-MB-231 and colon cancer cell line HCT116. The most potent derivatives Pr-ADOTA and Pr-DAOTA had IC50 values of ∼80 nM for MDA-MB-231 but slightly higher for HCT116 in the low hundreds nM range. A 3D model assay of HCT116 spheroids was also used, mimicking a tumour environment, again both Pr-ADOTA and Pr-DAOTA were very active with IC50 values of 38 nM and 21 nM, respectively. Molecular modelling suggest that the planar derivatives intercalate between the base pairs of the DNA double helix. However, only modest DNA double stranded DNA cleavage was observed using the γH2AX assay as compared to camptothecin, a topoisomerase I poison suggesting a different mechanism. Finally, a robust density functional theory (DFT) model was built to predict the pK R+ stability values, i.e., to design derivatives, which predominantly have a non-intercalating buckled form in healthy tissues followed by a nucleophilic attach of water on the central carbon, but a planar form at relatively low pH values rendering them only cytotoxic in the interior of tumours.
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Affiliation(s)
- Euphemia Leung
- Auckland Cancer Society Research Centre , University of Auckland , Grafton , Auckland 1023 , New Zealand
| | - Lisa I Pilkington
- School of Chemical Sciences , University of Auckland , City Centre , Auckland 1010 , New Zealand
| | - Mohinder M Naiya
- School of Chemical Sciences , University of Auckland , City Centre , Auckland 1010 , New Zealand
| | - David Barker
- School of Chemical Sciences , University of Auckland , City Centre , Auckland 1010 , New Zealand
| | - Ayesha Zafar
- School of Chemical Sciences , University of Auckland , City Centre , Auckland 1010 , New Zealand
| | - Chatchakorn Eurtivong
- Program of Chemical Biology , Chulabhorn Graduate Institute , Chulabhorn Royal Academy of Science , Bangkok 10210 , Thailand
| | - Jóhannes Reynisson
- School of Chemical Sciences , University of Auckland , City Centre , Auckland 1010 , New Zealand
- School of Pharmacy , Keele University , Hornbeam building , Staffordshire ST5 5BG , UK . ; Tel: +44 (0)1782 733985
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13
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Affiliation(s)
- John A. Joule
- Chemistry Department; The University of Manchester; Manchester M13 9PL UK
| | - Mercedes Álvarez
- Pharmacology; Toxicology and Medicinal Chemistry; Universitat de Barcelona; Joan XXIII, s/n E-08028 Barcelona Spain
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14
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Rosenberg M, Junker AKR, Sørensen TJ, Laursen BW. Fluorescence pH Probes Based on Photoinduced Electron Transfer Quenching of Long Fluorescence Lifetime Triangulenium Dyes. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201800266] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Martin Rosenberg
- Nano-Science Center and Department of ChemistryUniversity of Copenhagen Universitetsparken 5 DK-2100 Copenhagen Ø Denmark
| | - Anne Kathrine R. Junker
- Nano-Science Center and Department of ChemistryUniversity of Copenhagen Universitetsparken 5 DK-2100 Copenhagen Ø Denmark
| | - Thomas Just Sørensen
- Nano-Science Center and Department of ChemistryUniversity of Copenhagen Universitetsparken 5 DK-2100 Copenhagen Ø Denmark
| | - Bo W. Laursen
- Nano-Science Center and Department of ChemistryUniversity of Copenhagen Universitetsparken 5 DK-2100 Copenhagen Ø Denmark
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15
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Morel E, Beauvineau C, Naud-Martin D, Landras-Guetta C, Verga D, Ghosh D, Achelle S, Mahuteau-Betzer F, Bombard S, Teulade-Fichou MP. Selectivity of Terpyridine Platinum Anticancer Drugs for G-quadruplex DNA. Molecules 2019; 24:molecules24030404. [PMID: 30678027 PMCID: PMC6385020 DOI: 10.3390/molecules24030404] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/18/2019] [Accepted: 01/22/2019] [Indexed: 01/23/2023] Open
Abstract
Guanine-rich DNA can form four-stranded structures called G-quadruplexes (G4s) that can regulate many biological processes. Metal complexes have shown high affinity and selectivity toward the quadruplex structure. Here, we report the comparison of a panel of platinum (II) complexes for quadruplex DNA selective recognition by exploring the aromatic core around terpyridine derivatives. Their affinity and selectivity towards G4 structures of various topologies have been evaluated by FRET-melting (Fluorescence Resonance Energy Transfert-melting) and Fluorescent Intercalator Displacement (FID) assays, the latter performed by using three different fluorescent probes (Thiazole Orange (TO), TO-PRO-3, and PhenDV). Their ability to bind covalently to the c-myc G4 structure in vitro and their cytotoxicity potential in two ovarian cancerous cell lines were established. Our results show that the aromatic surface of the metallic ligands governs, in vitro, their affinity, their selectivity for the G4 over the duplex structures, and platination efficiency. However, the structural modifications do not allow significant discrimination among the different G4 topologies. Moreover, all compounds were tested on ovarian cancer cell lines and normal cell lines and were all able to overcome cisplatin resistance highlighting their interest as new anticancer drugs.
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Affiliation(s)
- Elodie Morel
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Claire Beauvineau
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Delphine Naud-Martin
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Corinne Landras-Guetta
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Daniela Verga
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Deepanjan Ghosh
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Sylvain Achelle
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- University Rennes, CNRS, ISCR-UMR 6226, F-35000 Rennes, France.
| | - Florence Mahuteau-Betzer
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Sophie Bombard
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
| | - Marie-Paule Teulade-Fichou
- Institut Curie, PSL Research University, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS-UMR 9187, INSERM U1196, F-91405 Orsay, France.
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16
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Hu MH, Zhou J, Luo WH, Chen SB, Huang ZS, Wu R, Tan JH. Development of a Smart Fluorescent Sensor That Specifically Recognizes the c-MYC G-Quadruplex. Anal Chem 2019; 91:2480-2487. [DOI: 10.1021/acs.analchem.8b05298] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Ming-Hao Hu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
- School of Pharmaceutical Sciences, Shenzhen University Health Science Center, Shenzhen 518060, China
| | - Jingwei Zhou
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Wen-Hua Luo
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Shuo-Bin Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Zhi-Shu Huang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Ruibo Wu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
| | - Jia-Heng Tan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou 510006, China
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17
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Delgado IH, Pascal S, Besnard C, Voci S, Bouffier L, Sojic N, Lacour J. C-Functionalized Cationic Diazaoxatriangulenes: Late-Stage Synthesis and Tuning of Physicochemical Properties. Chemistry 2018; 24:10186-10195. [PMID: 29698563 PMCID: PMC6099254 DOI: 10.1002/chem.201801486] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Indexed: 01/24/2023]
Abstract
A series of nine C-functionalized cationic diazaoxatriangulene (DAOTA) dyes have been successfully synthesized and fully characterized, including X-ray structural analysis of four derivatives. The introduction of electron-withdrawing or -donating functions enables the tuning of both electro- and photochemical properties with, for instance, two consecutive (reversible) reductions or oxidations observed for nitro or amino derivatives, respectively. The substituents also impacted on the optical properties, with absorption maxima varying from λ=528 to 640 nm and fluorescence being shifted from the yellow to the red range, up to λ=656 nm.
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Affiliation(s)
- Irene Hernández Delgado
- Department of Organic ChemistryUniversity of Genevaquai Ernest Ansermet 301211Geneva 4Switzerland
| | - Simon Pascal
- Department of Organic ChemistryUniversity of Genevaquai Ernest Ansermet 301211Geneva 4Switzerland
| | - Céline Besnard
- Laboratory of CrystallographyUniversity of Genevaquai Ernest Ansermet 241211Geneva 4Switzerland
| | - Silvia Voci
- Univ. Bordeaux, CNRS, Bordeaux INPISM, UMR 525533400TalenceFrance
| | - Laurent Bouffier
- Univ. Bordeaux, CNRS, Bordeaux INPISM, UMR 525533400TalenceFrance
| | - Neso Sojic
- Univ. Bordeaux, CNRS, Bordeaux INPISM, UMR 525533400TalenceFrance
| | - Jérôme Lacour
- Department of Organic ChemistryUniversity of Genevaquai Ernest Ansermet 301211Geneva 4Switzerland
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18
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Amor S, Yang SY, Wong JMY, Monchaud D. Cellular Detection of G-Quadruplexes by Optical Imaging Methods. ACTA ACUST UNITED AC 2017; 76:4.33.1-4.33.19. [PMID: 28862343 DOI: 10.1002/cpcb.29] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
G-quadruplexes (G4s) are higher-order nucleic acid structures that fold from guanine (G)-rich DNA and RNA strands. This field of research gains traction as a major chemical biology area since it aims at uncovering many key cellular mechanisms in which quadruplexes are involved. The wealth of knowledge acquired over the past three decades strongly supports pivotal roles of G4 in the regulation of gene expression at both transcriptional (DNA quadruplexes) and translational levels (RNA quadruplexes). Recent biochemical discoveries uncovered myriad of additional G4 actions: from chromosomal stability to the firing of replication origins, from telomere homeostasis to functional dysregulations underlying genetic diseases (including cancers and neurodegeneration). Here, we listed a repertoire of protocols that we have developed over the past years to visualize quadruplexes in cells. These achievements were made possible thanks to the discovery of a novel family of versatile quadruplex-selective fluorophores, the twice-as-smart quadruplex ligands named TASQ (for template-assembled synthetic G-quartet). The versatility of this probe allows for multiple imaging techniques in both fixed and live cells, including the use of the multiphoton microscopy, confocal microscopy, and real-time fluorescent image collection. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Souheila Amor
- Institut de Chimie Moléculaire, ICMUB CNRS UMR6302, UBFC Dijon, France
| | - Sunny Y Yang
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, Canada
| | - Judy M Y Wong
- Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, Canada
| | - David Monchaud
- Institut de Chimie Moléculaire, ICMUB CNRS UMR6302, UBFC Dijon, France
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19
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Hitzenberger JF, Uhl A, Schatz J, Drewello T. Influence of electronic and molecular structure on the fragmentation dynamic of even-electron carbocationic triangulenes and helicenes in the gas phase. JOURNAL OF MASS SPECTROMETRY : JMS 2017; 52:174-181. [PMID: 28098959 DOI: 10.1002/jms.3912] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 01/10/2017] [Accepted: 01/13/2017] [Indexed: 06/06/2023]
Abstract
Stable, long-lived organic cations are directly transferred by electrospray ionization (ESI) from solution into the gas phase where their collision-induced dissociations (CID) are studied by tandem mass spectrometry. Three related types of triphenyl carbenium ions are investigated, in which the meta positions are either substituted by methoxy groups or tertiary nitrogen bridges, including tetramethoxyphenylacridinium (TMPA+ ), dimethoxyquinacridinium (DMQA+ ), and triazatriangulenium (TATA+ ) cations. These ions are triangular in shape with increasing degrees of planarity. Fragmentation occurs at the periphery of the triangular molecule, involving the methoxy groups and the substituent of the nitrogen bridge. Each initial precursor cation is an even electron (EE) system and shows competing dissociations into both even (EE) and odd electron (OE) fragment ions. The latter reaction is a breach of the classic 'even-electron rule' in mass spectrometry. While the EE fragment dissociates similar to the precursor, the OE fragment ion shows a rich radical-induced fragmentation pattern. Two driving forces direct the fragmentation of the EE precursor ion toward OE fragment ions, including the release of stabilized radicals and the extension of the π-system by increasing planarization of the triangulene core. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Jakob Felix Hitzenberger
- Physical Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Agnes Uhl
- Organic Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Henkestraße 42, 91054, Erlangen, Germany
| | - Jürgen Schatz
- Organic Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Henkestraße 42, 91054, Erlangen, Germany
| | - Thomas Drewello
- Physical Chemistry I, Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 3, 91058, Erlangen, Germany
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20
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Bogh S, Simmermacher M, Westberg M, Bregnhøj M, Rosenberg M, De Vico L, Veiga M, Laursen BW, Ogilby PR, Sauer SPA, Sørensen TJ. Azadioxatriangulenium and Diazaoxatriangulenium: Quantum Yields and Fundamental Photophysical Properties. ACS OMEGA 2017; 2:193-203. [PMID: 31457221 PMCID: PMC6641101 DOI: 10.1021/acsomega.6b00211] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 01/06/2017] [Indexed: 05/24/2023]
Abstract
Over the last decade, we have investigated and exploited the photophysical properties of triangulenium dyes. Azadioxatriangulenium (ADOTA) and diazaoxatriangulenium (DAOTA), in particular, have features that make them useful in various fluorescence-based technologies (e.g., bioimaging). Through our work with ADOTA and DAOTA, we became aware that the reported fluorescence quantum yields (ϕfl) for these dyes are lower than their actual values. We thus set out to further investigate the fundamental structure-property relationships in these unique conjugated cationic systems. The nonradiative processes in the systems were explored using transient absorption spectroscopy and time-resolved emission spectroscopy in combination with computational chemistry. The influence of molecular oxygen on the fluorescence properties was explored, and the singlet oxygen sensitization efficiencies of ADOTA and DAOTA were determined. We conclude that, for these dyes, the amount of nonradiative deactivation of the first excited singlet state (S1) of the azaoxa-triangulenium fluorophores is low, that the rate of such deactivation is slower than what is observed in common cationic dyes, that there are no observable radiative transitions occurring from the first excited triplet state (T1) of these dyes, and that the efficiency of sensitized singlet oxygen production is low (ϕΔ ≤ 10%). These photophysical results provide a solid base upon which technological applications of these fluorescent dyes can be built.
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Affiliation(s)
- Sidsel
A. Bogh
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
| | - Mats Simmermacher
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
| | - Michael Westberg
- Department
of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Mikkel Bregnhøj
- Department
of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Martin Rosenberg
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
| | - Luca De Vico
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
| | - Manoel Veiga
- PicoQuant
GmbH, Rudower Chaussee
29, 12489 Berlin, Germany
| | - Bo W. Laursen
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
| | - Peter R. Ogilby
- Department
of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Stephan P. A. Sauer
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
| | - Thomas Just Sørensen
- Nano-Science
Center & Department of Chemistry, University
of Copenhagen, Universitetsparken
5, 2100 København
Ø, Denmark
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21
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Hirose T, Sasatsuki K, Noguchi H, Yokoyama S, Matsuda K. Aggregation of 4,8,12-Triazatriangulene Cation with Amphiphilic Side Chains: Emission Properties in Solution, in Aggregates, and in the Solid State. CHEM LETT 2016. [DOI: 10.1246/cl.160453] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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22
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Kotar A, Wang B, Shivalingam A, Gonzalez-Garcia J, Vilar R, Plavec J. NMR Structure of a Triangulenium-Based Long-Lived Fluorescence Probe Bound to a G-Quadruplex. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606877] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Anita Kotar
- Slovenian NMR Center; National Institute of Chemistry; Hajdrihova 19 1000 Ljubljana Slovenia
| | - Baifan Wang
- Slovenian NMR Center; National Institute of Chemistry; Hajdrihova 19 1000 Ljubljana Slovenia
| | - Arun Shivalingam
- Department of Chemistry; Imperial College London; South Kensington London SW7 2AZ UK
| | - Jorge Gonzalez-Garcia
- Department of Chemistry; Imperial College London; South Kensington London SW7 2AZ UK
| | - Ramon Vilar
- Department of Chemistry; Imperial College London; South Kensington London SW7 2AZ UK
| | - Janez Plavec
- Slovenian NMR Center; National Institute of Chemistry; Hajdrihova 19 1000 Ljubljana Slovenia
- EN-FIST Center of Excellence; Trg OF 13 1000 Ljubljana Slovenia
- Faculty of Chemistry and Chemical Technology; University of Ljubljana; Večna pot 113 Ljubljana Slovenia
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23
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Kotar A, Wang B, Shivalingam A, Gonzalez-Garcia J, Vilar R, Plavec J. NMR Structure of a Triangulenium-Based Long-Lived Fluorescence Probe Bound to a G-Quadruplex. Angew Chem Int Ed Engl 2016; 55:12508-11. [PMID: 27577037 DOI: 10.1002/anie.201606877] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Indexed: 12/31/2022]
Abstract
An NMR structural study of the interaction between a small-molecule optical probe (DAOTA-M2) and a G-quadruplex from the promoter region of the c-myc oncogene revealed that they interact at 1:2 binding stoichiometry. NMR-restrained structural calculations show that binding of DAOTA-M2 occurs mainly through π-π stacking between the polyaromatic core of the ligand and guanine residues of the outer G-quartets. Interestingly, the binding affinities of DAOTA-M2 differ by a factor of two for the outer G-quartets of the unimolecular parallel G-quadruplex under study. Unrestrained MD calculations indicate that DAOTA-M2 displays significant dynamic behavior when stacked on a G-quartet plane. These studies provide molecular guidelines for the design of triangulenium derivatives that can be used as optical probes for G-quadruplexes.
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Affiliation(s)
- Anita Kotar
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Baifan Wang
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Arun Shivalingam
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Jorge Gonzalez-Garcia
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Ramon Vilar
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia. .,EN-FIST Center of Excellence, Trg OF 13, 1000, Ljubljana, Slovenia. .,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, Ljubljana, Slovenia.
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24
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Shivalingam A, Vyšniauskas A, Albrecht T, White AJP, Kuimova MK, Vilar R. Trianguleniums as Optical Probes for G-Quadruplexes: A Photophysical, Electrochemical, and Computational Study. Chemistry 2016; 22:4129-39. [PMID: 26880483 PMCID: PMC4991273 DOI: 10.1002/chem.201504099] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Indexed: 01/27/2023]
Abstract
Nucleic acids can adopt non-duplex topologies, such as G-quadruplexes in vitro. Yet it has been challenging to establish their existence and function in vivo due to a lack of suitable tools. Recently, we identified the triangulenium compound DAOTA-M2 as a unique fluorescence probe for such studies. This probe's emission lifetime is highly dependent on the topology of the DNA it interacts with opening up the possibility of carrying out live-cell imaging studies. Herein, we describe the origin of its fluorescence selectivity for G-quadruplexes. Cyclic voltammetry predicts that the appended morpholino groups can act as intra- molecular photo-induced electron transfer (PET) quenchers. Photophysical studies show that a delicate balance between this effect and inter-molecular PET with nucleobases is key to the overall fluorescence enhancement observed upon nucleic acid binding. We utilised computational modelling to demonstrate a conformational dependence of intra-molecular PET. Finally, we performed orthogonal studies with a triangulenium compound, in which the morpholino groups were removed, and demonstrated that this change inverts triangulenium fluorescence selectivity from G-quadruplex to duplex DNA, thus highlighting the importance of fine tuning the molecular structure not only for target affinity, but also for fluorescence response.
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Affiliation(s)
- Arun Shivalingam
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Aurimas Vyšniauskas
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Tim Albrecht
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Andrew J P White
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK
| | - Marina K Kuimova
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK.
| | - Ramon Vilar
- Department of Chemistry, Imperial College London, South Kensington, London, SW7 2AZ, UK.
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